Development and Research of the Current Measurement Scheme for Insulation Tests with High Voltage Industrial Frequency

Abstract

When designing test voltage sources with AC power frequency for regular assessment of the insulation quality of high-voltage equipment, the task is to measure the current flowing through the test object. The authors have developed an algorithm and proposed a technical solution for measuring the current flowing through the test object when testing insulation with an alternating sinusoidal voltage of industrial frequency, which uses a precision resistor, an isolation amplifier and an ADC of a microcontroller. The developed algorithm for the study of the circuit for measuring the alternating current flowing through the test object when testing the insulation with an alternating sinusoidal voltage of the industrial frequency makes it possible to increase the speed of developing measuring devices. During the study of the stand of the circuit for measuring the alternating current flowing through the tested object when testing the insulation with an alternating sinusoidal voltage of industrial frequency, an experimental industrial sample was created that makes it possible to measure the rms current value within the range from 1 mA to 320 mA. The use of the developed circuit for measuring the current flowing through the test object when testing insulation with an alternating sinusoidal voltage of industrial frequency, allows you to obtain the rms current value in real time, and, therefore, to quickly monitor the current in high-voltage circuits for continuous monitoring. The introduction of this sample will make it possible, on its basis, to create a number of digital measuring milliammeters that allow measuring alternating current in high-voltage test installations for testing the insulation of objects from 15 nF to 200 nF, in the range from 1 mA to 1000 mA. The results obtained can be used in high voltage technology to study circuits for measuring the current flowing through the test object when testing insulation with an alternating sinusoidal voltage of industrial frequency.